Wireless EV charging nears plug-in efficiency levels

ORNL's proving its charger's worth using a Toyota RAV4 EV with a special 10kWh battery adapted for wireless charging.

Oak Ridge National Laboratory

Have you used wireless charging with a smartphone? It's helpful, but a cable gets the job done faster and without much of the waste heat that comes along with the current state of wireless chargers. Those are even bigger problems when you scale up charging to an electric vehicle, but we're getting closer to solving them.

The Department of Energy's Oak Ridge National Laboratory (ORNL) is currently demonstrating that high levels of efficiency can be achieved with wireless EV chargers. The lab is currently running a 20kW charger at 90 percent efficiency. That's enough juice to provide about 60 miles of charge in an hour or two.

This is mostly a proof of concept, not quite ready for the market just yet. That said, ORNL's planning on developing a 50kW wireless charger next, which would provide charging speeds on par with some of the fastest plug-in offerings. When that point is reached, and costs are low enough to jive with buyers, that's when we can expect to see a real push to introduce wireless charging on a wide scale.

ORNL also sees wireless charging as an important step in introducing full-on autonomous vehicles. If the cars can drive around and charge without human intervention, then you'd start seeing the materialization of this driving-free utopia that some are keen to introduce as soon as possible.

Of course, it takes special equipment to charge an EV wirelessly. Right now, there are no manufacturer solutions for wireless charging, although there are aftermarket retrofit kits available.